Centers for Disease Control, tobacco smoke injures your lungs and leads to lung diseases like chronic obstructive pulmonary disease COPD , emphysema, and chronic bronchitis. Tobacco damage is cumulative. Indoor pollution from secondhand smoke, mold, dust, household chemicals, radon, or asbestos can damage your lungs and worsen existing lung disease.
Chronic smoking is a known cause of lung disease. Other causes include genetics, infections, or compromised immune systems. Chemotherapy and radiation treatments for cancer can also contribute to lung disease. Sometimes the cause of lung disease is unknown. Lung disease has many types, all of which affect your breathing.
Here are some common lung diseases:. The normal aging process can slow down your respiratory system. You may notice that your lung capacity is lessened, or that your chest muscles are weaker. Read more about growing older and your lung health.
Use an air cleaner or purifier at work or at home to reduce indoor dust and fumes. On days when the air quality index AQI is at an unhealthy range, keep your exposure minimal by keeping doors and windows closed and circulating air inside.
You can also check out blogs for people trying to quit. The respiratory system with its millions of alveoli is a complex machine. We just breathe in and out in the normal course of our day. Breathing exercises to increase lung capacity may be a good place to start. Here are five pieces of advice to maintain optimal lung health and breathing capacity, from staying far away from cigarettes to adopting a consistent….
Lung conditions like COPD can significantly reduce lung function and your ability to breathe comfortably. Read on to learn how to increase lung…. A new study finds that cinnamon flavors can hurt lung tissue. A pulmonologist is a doctor who focuses on the respiratory system. Discover the conditions they treat such as COPD , exams they conduct, and much…. An incentive spirometer is a device that can help you strengthen your lungs. Learn how it works, who it helps, and where to get one. The respiratory tract is coated with mucus to seal the tissues from direct contact with air.
Mucus is high in water. As air crosses these surfaces of the mucous membranes, it picks up water. These processes help equilibrate the air to the body conditions, reducing any damage that cold, dry air can cause. Particulate matter that is floating in the air is removed in the nasal passages via mucus and cilia. The processes of warming, humidifying, and removing particles are important protective mechanisms that prevent damage to the trachea and lungs. Thus, inhalation serves several purposes in addition to bringing oxygen into the respiratory system.
From the nasal cavity, air passes through the pharynx throat and the larynx voice box , as it makes its way to the trachea Figure The main function of the trachea is to funnel the inhaled air to the lungs and the exhaled air back out of the body.
The human trachea is a cylinder about 10 to 12 cm long and 2 cm in diameter that sits in front of the esophagus and extends from the larynx into the chest cavity where it divides into the two primary bronchi at the midthorax.
It is made of incomplete rings of hyaline cartilage and smooth muscle Figure The trachea is lined with mucus-producing goblet cells and ciliated epithelia. The cilia propel foreign particles trapped in the mucus toward the pharynx. The cartilage provides strength and support to the trachea to keep the passage open. The forced exhalation helps expel mucus when we cough. The end of the trachea bifurcates divides to the right and left lungs. The lungs are not identical.
The right lung is larger and contains three lobes, whereas the smaller left lung contains two lobes Figure The muscular diaphragm, which facilitates breathing, is inferior below to the lungs and marks the end of the thoracic cavity.
In the lungs, air is diverted into smaller and smaller passages, or bronchi. Air enters the lungs through the two primary main bronchi singular: bronchus. Each bronchus divides into secondary bronchi, then into tertiary bronchi, which in turn divide, creating smaller and smaller diameter bronchioles as they split and spread through the lung.
Like the trachea, the bronchi are made of cartilage and smooth muscle. At the bronchioles, the cartilage is replaced with elastic fibers. In humans, bronchioles with a diameter smaller than 0. They lack cartilage and therefore rely on inhaled air to support their shape. As the passageways decrease in diameter, the relative amount of smooth muscle increases.
The terminal bronchioles subdivide into microscopic branches called respiratory bronchioles. The respiratory bronchioles subdivide into several alveolar ducts. Numerous alveoli and alveolar sacs surround the alveolar ducts. The alveolar sacs resemble bunches of grapes tethered to the end of the bronchioles Figure In the acinar region, the alveolar ducts are attached to the end of each bronchiole.
At the end of each duct are approximately alveolar sacs, each containing 20 to 30 alveoli that are to microns in diameter. Gas exchange occurs only in alveoli. Alveoli are made of thin-walled parenchymal cells, typically one-cell thick, that look like tiny bubbles within the sacs. Alveoli are in direct contact with capillaries one-cell thick of the circulatory system. Such intimate contact ensures that oxygen will diffuse from alveoli into the blood and be distributed to the cells of the body.
In addition, the carbon dioxide that was produced by cells as a waste product will diffuse from the blood into alveoli to be exhaled. The anatomical arrangement of capillaries and alveoli emphasizes the structural and functional relationship of the respiratory and circulatory systems. This organization produces a very large surface area that is available for gas exchange. The surface area of alveoli in the lungs is approximately 75 m 2. This large surface area, combined with the thin-walled nature of the alveolar parenchymal cells, allows gases to easily diffuse across the cells.
Watch the following video to review the respiratory system. The air that organisms breathe contains particulate matter such as dust, dirt, viral particles, and bacteria that can damage the lungs or trigger allergic immune responses.
The respiratory system contains several protective mechanisms to avoid problems or tissue damage. In the nasal cavity, hairs and mucus trap small particles, viruses, bacteria, dust, and dirt to prevent their entry. If particulates do make it beyond the nose, or enter through the mouth, the bronchi and bronchioles of the lungs also contain several protective devices. Energy is produced by burning molecules in food, which is done by the process of oxidation whereby food molecules are combined with Inhaled oxygen enters the lungs and reaches the alveoli.
The layers of cells lining the alveoli and the surrounding capillaries are each only one cell thick and are in very close contact with each other. Oxygen passes quickly through this air-blood barrier into the blood in the capillaries.
Similarly, carbon dioxide passes from the blood into the alveoli and is then exhaled. Oxygenated blood travels from the lungs through the pulmonary veins and into the left side of the heart, which pumps the blood to the rest of the body see Function of the Heart Function of the Heart The heart and blood vessels constitute the cardiovascular circulatory system.
The heart pumps the blood to the lungs so it can pick up oxygen and then pumps oxygen-rich blood to the body Oxygen-deficient, carbon dioxide-rich blood returns to the right side of the heart through two large veins, the superior vena cava and the inferior vena cava.
Then the blood is pumped through the pulmonary artery to the lungs, where it picks up oxygen and releases carbon dioxide. To support the absorption of oxygen and release of carbon dioxide, about 5 to 8 liters about 1. At the same time, a similar volume of carbon dioxide moves from the blood to the alveoli and is exhaled. During exercise, it is possible to breathe in and out more than liters about 26 gallons of air per minute and extract 3 liters a little less than 1 gallon of oxygen from this air per minute.
The rate at which oxygen is used by the body is one measure of the rate of energy expended by the body. Breathing in and out is accomplished by respiratory muscles Control of Breathing Breathing is usually automatic, controlled subconsciously by the respiratory center at the base of the brain.
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